Add an option for skipping inline comments (#74)

* Add an option for skipping inline comments
* format

src/parser/parse-shaders.js

@@ -2,8 +2,11 @@ import { scan, iterator, Token } from './tokenizer.js';
 import { is_empty } from '../utils/index.js';
 
 function parse(input) {
-  input = input.replace(/\/\/[^\n]*(\n|$)/mg, ''); // remove single-line comment
-  let iter = iterator(removeParens(scan(input, true)));
+  let scanOptions = {
+    preserveLineBreak: true,
+    ignoreInlineComment: true,
+  };
+  let iter = iterator(removeParens(scan(input, scanOptions)));
   let stack = [];
   let tokens = [];
   let identifier;

src/parser/tokenizer.js

@@ -24,6 +24,7 @@ const is = {
   dots:          (a, b) => is.dot(a) && is.dot(b),
   letter:        (a, b) => String(a).toLowerCase() == String(b).toLowerCase(),
   comment:       (a, b) => a == '/' && b == '*',
+  inlineComment: (a, b) => a == '/' && b === '/',
   selfClosedTag: (a, b) => a == '/' && b == '>',
   closedTag:     (a, b) => a == '<' && b == '/',
 }
@@ -63,7 +64,7 @@ function iterator(input) {
     },
     next(n = 1) {
       let next = input[pointer += n];
-      if (next == '\n') row++, col = 0;
+      if (next === '\n') row++, col = 0;
       else col += n;
       return next;
     },
@@ -90,6 +91,12 @@ function skipComments(iter) {
   }
 }
 
+function skipInlineComments(iter) {
+  while (iter.next()) {
+    if (iter.curr() === '\n') break;
+  }
+}
+
 function ignoreSpacingSymbol(value) {
    return [':', ';', ',', '{', '}', '(', ')', '[', ']'].includes(value);
 }
@@ -158,7 +165,7 @@ function last(array) {
   return array[array.length - 1];
 }
 
-function scan(source, preserveLineBreak = false) {
+function scan(source, options = {}) {
   let iter = iterator(String(source).trim());
   let tokens = [];
   let quoteStack = [];
@@ -168,6 +175,9 @@ function scan(source, preserveLineBreak = false) {
     if (is.comment(curr, next)) {
       skipComments(iter);
     }
+    else if (options.ignoreInlineComment && is.inlineComment(curr, next)) {
+      skipInlineComments(iter);
+    }
     else if (is.hex(curr, next, next2)) {
       let num = readHexNumber(iter);
       tokens.push(new Token({
@@ -233,7 +243,7 @@ function scan(source, preserveLineBreak = false) {
         if (ignoreLeft || ignoreRight)  {
           continue;
         } else {
-          spaces = preserveLineBreak ? curr : ' ';
+          spaces = options.preserveLineBreak ? curr : ' ';
         }
       }
       if (tokens.length && (next && next.trim())) {

test/parse-shaders.js

@@ -116,3 +116,23 @@ test('handle nested parens', t => {
   }
   compare(t, input, result);
 });
+
+test('ignore comments', t => {
+  let input = `
+    // this is inline comment
+    // this is another inline comment
+    fragment {
+      void main() {
+        /**
+         * more comments
+         */
+        float PI = /*pi value*/3.14159;
+      }
+    }
+  `;
+  let result = {
+    fragment: 'void main(){float PI = 3.14159;}',
+    textures: []
+  }
+  compare(t, input, result);
+});